TABLE 2.
Percentage of Salmonella isolates that were resistant to specific antimicrobials grouped by period and treatmenta
| Antimicrobial | Period | % Resistant isolates (SE)b
|
|||||
|---|---|---|---|---|---|---|---|
| Continuous tylosin (n1 = 16, n2 = 3) | Continuous CTC (n1 = 30, n2 = 11) | Pulse tylosin (n1 = 19, n2 = 14) | Pulse CTC (n1 = 44, n2 = 30) | No antimicrobial (n1 = 8, n2 = 10) | All isolates (n1 = 117, n2 = 68) | ||
| Amoxicillin-clavulanic | 1 | 0.0 | 0.0 | 5.3 (6.8) | 0.0 | 0.0 | 0.9 (0.9) |
| acid | 2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| Ampicillin | 1 | 6.2 (0.0) | 25.8 (24.1) | 73.7 (26.3) | 27.3 (12.7) | 37.5 (13.6) | 32.2 (10.7) |
| 2 | 33.3 (16.1) | 18.2 (18.7) | 50.0 (22.6) | 60.0 (17.2) | 10.0 (7.2) | 42.6 (12.5) | |
| Ceftiofur | 1 | 0.0 | 3.2 (2.0) | 0.0 | 0.0 | 0.0 | 0.8 (0.8) |
| 2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
| Cephalothin | 1 | 0.0 | 0.0 | 0.0 | 0.0 | 12.5 (4.5) | 0.9 (0.9) |
| 2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | |
| Chloramphenicol | 1 | 0.0 | 0.0 | 15.8 (12.9) | 0.0 | 0.0 | 2.5 (2.0) |
| 2 | 0.0 | 0.0 | 35.7 (30.3) | 10.0 (5.4) | 0.0 | 11.8 (7.4) | |
| Kanamycin | 1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| 2 | 0.0 | 0.0 | 0.0 | 0.0 | 10.0 (7.2) | 1.5 (1.5) | |
| Streptomycin | 1 | 100.0 | 87.1 (12.9) | 100.0 | 100.0 | 100.0 | 96.6 (3.5) |
| 2 | 66.7 (32.2) | 90.9 (10.2) | 85.7 (15.5) | 100.0 | 100.0 | 94.1 (4.0) | |
| Sulfamethoxazole | 1 | 93.8 (0.0) | 80.6 (15.3) | 89.5 (6.0) | 88.6 (2.9) | 100.0 | 88.1 (4.2) |
| 2 | 66.7 (32.2) | 81.8 (14.4) | 85.7 (15.5) | 100.0 | 90.0 (7.2) | 91.2 (4.8) | |
| Tetracycline | 1 | 100.0 | 96.8 (2.0) | 100.0 | 100.0 | 87.5 (13.6) | 98.3 (1.2) |
| 2 | 66.7 (32.2) | 100.0 | 85.7 (15.5) | 96.7 (4.0) | 100.0 | 94.1 (4.0) | |
a
Pansusceptible antimicrobials (amikacin, cefoxitin, ciprofloxacin, gentamicin, nalidixic acid, and trimethoprim-sulfamethoxazole) were excluded from this table.
b
n1 and n2 represent the number of isolates in periods 1 and 2, respectively.